The variable radial depth of cut in finishing machining of thin-walled blade based on the stable-state deformation field

Abstract

Due to the low stiffness of the thin-walled part, the larger deformation error occurs in the milling process, and the machining precision and quality cannot be satisfied. Previous studies of the tool path generation methods for the deformation error control mainly focused on the deformation calculation of the cutting block and lacked how to control the machining deformation of the complex free-form surface of the thin-walled blade by the generated tool path. This paper firstly establishes the elastic deformation error model of the thin-walled part milling process depending on the stiffness matrix of the workpiece before the cutting process. Furthermore, the cutting force model in ball-end milling and the stable-state deformation field are studied to calculate the cutting contact points sequence with less machining deformation error for the tool path planning process. The radial depth of cut of the generated tool path is optimized with different strategies to calculate the suitable cutting contact points for deformation control of the thin-walled part milling process by applying the relationship between the cutting parameters and elastic deformation. Finally, thin-walled blades are machined with four different cutting paths. The measured results demonstrate that the optimized tool paths are effective for deformation error control of the thin-walled blades milling process considering the machining precision and efficiency.